2) Bitcoin difficulty will rise in the short term due to the new miners coming from the namecoin chain.
2: No. Total hashrate for namecoin right now is something like 30Ghash, not enough to have any kind of impact
So you mean, "Yes, but not in a meaningful way".
3) The bitcoin value will be equal (or higher if the increased difficulty also increases adoption).
3: No. Bitcoin value would dip somewhat as speculators traded them for namecoins, and then namecoin hoarders cashed out their bitcoins.
I guess you're right, but speculators could put dollars into namecoin instead of bitcoins. Only if they "quit speculating with bitcoins" for speculating with namecoins btc losses value.
5) The diffuculty/value of both currencies will rise.
5: No. Namecoin value would rise but not by a vast amount. Bitcoin value would fall.
Bitcoin value could fall or not. Only speculators leaving bitcoin will make its value fall.
Namecoin value will rise proportionally to the increase in acceptance that the increase in difficulty produces (Plus the effect of speculators).